1. Field of the Invention
This invention relates to a zoom lens capable of accomplishing macro-photography.
2. Description of the Prior Art
Numerous zoom lenses including a wide angle of view and having a relatively wide magnification change area have recently been proposed, but most of them have been long in the shortest photographing distance as compared with single focal length objective lenses having the same degree of focal length, and the shortest photographing distance and the maximum photographing magnification have still been insufficient in such zoom lenses. In order to overcome this disadvantage, use has been made of a method of shortening the photographing distance by moving the lens groups along the optic axis other than the lens group moved from the ordinary focusing, that is, the so-called macro-photography system. However, in the conventional macro-photography system, the shorter the photographing distance, the more substantial the occurrence of aberrations and therefore, in macro-photography, the imaging performance is deteriorated and however excellent in the imaging performance in the infinity photographing stage, it has been difficult to maintain the good performance in a short distance as well.